1. Field of the Invention
This invention relates to electrical cable connectors. More particularly, the invention relates to a coaxial cable connector with an inner conductor to inner contact longitudinal retention interconnection.
2. Description of Related Art
Coaxial cable connectors are used, for example, in communication systems requiring a high level of precision and reliability.
To create a secure mechanical and optimized electrical interconnection between the cable and the connector, prior coaxial connectors have utilized circumferential contact between a leading edge of the coaxial cable outer conductor and the connector body, such as a flared end of the outer conductor that is clamped against an annular wedge surface of the connector body, via a coupling nut. With the outer conductor mechanically secured, the inner conductor may be allowed to longitudinally float, electrically contacted by a bias-type contact mechanism such as spring fingers engaging the inner conductor along an outer diameter surface, or, if the inner conductor is hollow, along an inner sidewall of the inner conductor bore. Representative of this technology is commonly owned U.S. Pat. No. 5,795,188 issued Aug. 18, 1998 to Harwath.
Where the attached coaxial cable has an extended length, variances between the thermal expansion characteristics of the inner and outer conductor may become significant, resulting in unacceptable longitudinal movement of the inner conductor with respect to the inner contact. Also, longitudinal movement of the inner conductor with respect to the inner contact may introduce undesirable passive intermodulation (PIM) distortion.
Alternatively, prior connectors have provided mechanical interconnections between the inner conductor and the inner contact via a thread-driven radial expansion and/or direct threading of the inner contact into the bore of a hollow inner conductor. The threaded elements and/or screws required for these configurations may increase manufacturing costs and/or installation complexity.
Competition in the coaxial cable connector market has focused attention on improving electrical performance and minimization of overall costs, including materials costs, training requirements for installation personnel, reduction of dedicated installation tooling and the total number of required installation steps and/or operations.
Therefore, it is an object of the invention to provide a coupling nut that overcomes deficiencies in the prior art.